Applitech worked with POMA-OTIS Transportation systems as a team to install and commission Automated People Movers (APMs) at the following locations:

• Huntsville Hospital in Huntsville, AL
• Detroit Airport - Midfield Terminal in Detroit, MI
• Minneapolis/St. Paul airport in Minneapolis, ME

Applitech provided the software programming for Automatic Train Operation (ATO) and Automatic Train Protection (ATP) systems. Applitech’s engineering group coordinated with the local trades and contracts for the installation and start up of the APMs. Applitech’s engineers built a GE Fanuc SCADA system to control, monitor, record and provide critical alarm for the Automatic People Movers. The entire operation of the train was automated including the start/stop of the train, train speeds and operation of the station doors.

The trains at Huntsville and Minneapolis airport had steel wheels and ran on steel tracks to accommodate for adverse weather conditions (snow & ice) while the train at the Detroit airport had a HOV-air system (traveled on air pads). Each train had a set of doors that opened when they were aligned with the station doors, which were commanded by the Automatic Train Operation (ATO) system. The train doors and station doors worked as a combined set of doors and opened and closed at the same time.

The guideway on which the train operated had various access points. Each guideway access point was monitored and an alarm generated when an unscheduled guideway access was detected. This alarm would kill power to the guideway and stop the train.

Controls engineers from Applitech worked closely with POMA-OTIS engineers to program and test the safety features necessary for safe operation of the APMs. The SCADA System screens were designed to the client’s and national safety standards.

Automatic Train Protection System (ATP)

• A triple modular redundant control system (TMR) was implemented to ensure the safe operation of the train. Automatic Train Protection (ATP) system software was developed that contained the safety critical features for the operation of the train. The ATP software fully complied with the guidelines of IEEE 730
• Switches were installed at every access point along the tracks to ensure that the train would stop if anyone were on the tracks while the train was in operation
  
• The ATP software kept track of the train position, direction and speed. The automatic anti-collision feature of the system prevented the trains from coming into close proximity of each other
• The ATP software was also responsible for prevention of terminal station over travel. If the train was approaching an end station and did not slow down at a predetermined rate while approaching the station, the ATP software would set the emergency brakes on the train and cut power to the guide-way to prevent the train from going past the terminal station and running into the station buffer
  
• The ATP software had an emergency condition collector module that collected the emergency stop conditions from a variety of modules. This offered ease in trouble shooting as it offered a single place to quickly review the cause of an emergency stop
• Any system integrity failures (self-test, and cross-check faults) would cause an alarm message to be printed in the central control room

Automatic Train Operation System (ATO)

• Automatic Train Operation (ATO) was programmed such that the train would travel at a preset speed between any two stations
• The distance between any two stations was divided into various zones and depending on the zone, the speed of the train would vary
  
• When the train was approaching a station, it would ramp down at a preset rate; come to a complete stop at the station and then the train doors as well as the station doors would open
• There were on-board announcements as well as passenger advisory announcements on the station when the train was approaching the station; it is on the station and just before departing the station. Details about passenger announcements are given in later sections
• While leaving a station the train ramps up at a predetermined rate taking into consideration a “jerk factor”. This is to make sure that the on-board passengers do not feel any jerks or excessive acceleration during the ramp up zone
  
• Automatic Train Operation (ATO) was programmed to respond to emergencies. In conjunction with the ATP, if an emergency were detected while the train was in normal operation, the train would go to the next station, drop-off all onboard passengers, then go the station where the emergency occurred skipping stops at any intermediate stations. This feature was useful especially in case of medical emergencies
  
• The ATO had a “Demand Mode”. This mode was used during off-peak hours for periods of low or irregular passenger demand. At times when there was no passenger demand, the operative on-call train was parked at either the Terminal Station or the Regional Station with both the train & platform doors closed

Central Control Operator Interface
The entire train movement will be monitored from a central control room. The SCADA system showing the status and movement of the train is located in the central control room. A central operator console was provided in the control room to take actions in case of ATO or ATP operating failures.